The present invention relates to an electric household appliance.
More specifically, the present invention relates to an electric household appliance corresponding to a rotary-drum home washing machine or laundry drier, to which the following description refers purely by way of example.
As is known, rotary-drum laundry driers substantially comprise a substantially parallelepiped-shaped casing; a cylindrical laundry drying tub or chamber fixed horizontally inside the casing, directly facing a laundry loading/unloading opening formed, in the front face of the casing; a door hinged to the front face of the casing to rotate to and from a work position closing the opening in the front face and sealing the drying tub; a cylindrical, perforated-wall laundry drum housed in axially rotating manner inside the wash/drying tub; and an electric motor for rotating the laundry drum about its longitudinal axis inside the drying tub.
Rotary-drum driers of the above type also comprise a hot-air generator for circulating inside the drying tub hot, dry air, which flows through the laundry drum and over the laundry inside to dry the laundry rapidly.
More specifically, some so-called “vented driers” feature an open-circuit, hot-air generator, which comprises an intake manifold connecting the rear wall of the drying tub to an air inlet; and an air exhaust manifold connected at one end to the front wall of the drying tub, and at the other end to an air exhaust outlet at the front of the casing.
The open-circuit, hot-air generator also comprises an electric heating element located along the intake manifold to heat the air before it is fed into the drying tub; and a ventilation device located along the exhaust manifold to draw air along the intake manifold, feed the hot air through the drying tub, and expel the moist air through the exhaust manifold.
The ventilation device is defined by a fan located along the exhaust manifold; and by a drive interposed between the drum electric motor and the fan to rotate the fan.
Using the same electric motor to simultaneously rotate the air intake/exhaust fan and the drum, as opposed to a specific electric motor for each device, has the major advantage of reducing the manufacturing cost of the drier.
On the other hand, in driers, with open-circuit, hot-air generators, the above solution makes it difficult to also implement a crease-removing function for which there is strong market demand, and which provides for feeding a jet of steam into the drying tub to eliminate or at any rate greatly reduce creasing of the fabrics during the drying cycle, and so make the fabrics easier to iron.
More specifically, whereas, when feeding the steam into the drying tub, the drying tub must be rotated to loosen and partly eliminate creasing of the fabrics inside the drum, operating the ventilation device simultaneously with rotation of the drying tub has the major drawback of practically expelling the steam immediately from the tub, thus reducing the crease-removing effectiveness of the steam. In other words, effective crease removal is prevented by the ventilation device immediately and continuously exhausting the steam.